宽雷诺数下肋参数对U 型内冷通道流动与 换热特性影响的实验研究

In order to study the influence of rib height to channel height ratio(e/H), rib spacing to rib height ratio(P/e) and rib angle(α)on the flow and heat transfer characteristics of ribbed U-type channels, the channel wall surface temperature distribution is measured using copper plate method combining thermocouple. Experimental study of the heat transfer characteristics on the surface of ribbed U-type channel with 6 different rib parameters is carried out. The ribbed channel has a square cross section, and the Reynolds number in this experiment is from 5.0×103 to 1.0×105. The experimental results show that with the increase of the e/H and Reynolds number, the convective heat transfer coefficient of the ribbed channel gradually increases, but the corresponding pressure loss increases significantly. As the e/H increases from 0.08 to 0.12, the friction factor of the channel almost doubles. For channel with e/H=0.08, among the three cases with the P/e being 6, 8, and 10, the convective heat transfer coefficient and pressure loss are highest when the ratio is 8. The angled rib can further enhance the convective heat transfer in ribbed channels compared to the 90° orthogonal rib. Additionally, the 75° rib is slightly more effective than the 60° rib. Within the experimental parameter range, the convective heat transfer coefficient is 1.9—3.0 times that of the smooth channel, and the drag coefficient is about 4—6 times that of the smooth channel. Considering heat transfer and flow resistance comprehensively, under the conditions of e/H=0.08, P/e=8, and α=45°, the thermal performance is the best.